US5098457A - Method and apparatus for producing elevated pressure nitrogen - Google Patents

Method and apparatus for producing elevated pressure nitrogen Download PDF

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Publication number
US5098457A
US5098457A US07/644,228 US64422891A US5098457A US 5098457 A US5098457 A US 5098457A US 64422891 A US64422891 A US 64422891A US 5098457 A US5098457 A US 5098457A
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nitrogen
column
enriched
oxygen
component
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US07/644,228
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English (en)
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Harry Cheung
Dante P. Bonaquist
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Praxair Technology Inc
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Union Carbide Industrial Gases Technology Corp
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Priority to US07/644,228 priority Critical patent/US5098457A/en
Assigned to UNION CARBIDE INDUSTRIAL GASES TECHNOLOGY CORPORATION, A CORP. OF DE reassignment UNION CARBIDE INDUSTRIAL GASES TECHNOLOGY CORPORATION, A CORP. OF DE ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: BONAQUIST, DANTE P., CHEUNG, HARRY
Priority to CA002059774A priority patent/CA2059774C/en
Priority to JP4029078A priority patent/JPH0789017B2/ja
Priority to ES92100936T priority patent/ES2065715T3/es
Priority to DE69200928T priority patent/DE69200928T2/de
Priority to MX9200264A priority patent/MX9200264A/es
Priority to EP92100936A priority patent/EP0496355B1/en
Priority to KR1019920000773A priority patent/KR0161296B1/ko
Priority to BR929200190A priority patent/BR9200190A/pt
Publication of US5098457A publication Critical patent/US5098457A/en
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Assigned to PRAXAIR TECHNOLOGY, INC. reassignment PRAXAIR TECHNOLOGY, INC. CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). EFFECTIVE ON 06/12/1992 Assignors: UNION CARBIDE INDUSTRIAL GASES TECHNOLOGY CORPORATION
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04248—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04284—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams
    • F25J3/0429—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams of feed air, e.g. used as waste or product air or expanded into an auxiliary column
    • F25J3/04303—Lachmann expansion, i.e. expanded into oxygen producing or low pressure column
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
    • F25J3/04187—Cooling of the purified feed air by recuperative heat-exchange; Heat-exchange with product streams
    • F25J3/04193—Division of the main heat exchange line in consecutive sections having different functions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
    • F25J3/04187—Cooling of the purified feed air by recuperative heat-exchange; Heat-exchange with product streams
    • F25J3/0423—Subcooling of liquid process streams
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
    • F25J3/04187—Cooling of the purified feed air by recuperative heat-exchange; Heat-exchange with product streams
    • F25J3/04236—Integration of different exchangers in a single core, so-called integrated cores
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04248—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04284—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04406—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air using a dual pressure main column system
    • F25J3/04424—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air using a dual pressure main column system without thermally coupled high and low pressure columns, i.e. a so-called split columns
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/20—Processes or apparatus using separation by rectification in an elevated pressure multiple column system wherein the lowest pressure column is at a pressure well above the minimum pressure needed to overcome pressure drop to reject the products to atmosphere
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/50—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column
    • F25J2200/54—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column in the low pressure column of a double pressure main column system
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2235/00—Processes or apparatus involving steps for increasing the pressure or for conveying of liquid process streams
    • F25J2235/42—Processes or apparatus involving steps for increasing the pressure or for conveying of liquid process streams the fluid being nitrogen
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2245/00—Processes or apparatus involving steps for recycling of process streams
    • F25J2245/42—Processes or apparatus involving steps for recycling of process streams the recycled stream being nitrogen
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S62/00—Refrigeration
    • Y10S62/939—Partial feed stream expansion, air

Definitions

  • This invention relates generally to the cryogenic separation of air to produce nitrogen and more particularly to the production of elevated pressure nitrogen.
  • High purity nitrogen at superatmospheric pressure is used in a number of applications such as blanketing, stirring, transporting and inerting in many industries such as glassmaking, aluminum production and electronics.
  • large quantities of nitrogen are used in enhanced oil or gas recovery operations after booster compression to high pressures.
  • One important method for producing nitrogen at elevated pressure is by the cryogenic rectification or separation of air using a single column.
  • a disadvantage with such a system is that it can efficiently produce elevated pressure nitrogen only at relatively low recovery rates.
  • single column systems can efficiently recover only about 42 percent of the feed air as product elevated pressure nitrogen.
  • the recovery of nitrogen by the cryogenic separation of air can be increased by employing a double column cryogenic rectification system wherein a higher pressure column and a lower pressure column are in heat exchange relation. While such a system improves nitrogen recovery, a significant amount of the nitrogen recovered is at a lower pressure. Thus, if elevated pressure nitrogen is required, the lower pressure nitrogen must be compressed to the higher pressure thus adding both capital costs and operating costs to the nitrogen production system.
  • a method for producing elevated pressure nitrogen with improved recovery comprising:
  • Another aspect of this invention comprises:
  • Apparatus for producing elevated pressure nitrogen with improved recovery comprising:
  • (B) means for providing fluid from the lower portion of the primary column into the top condenser
  • (F) means for recovering product from the primary column.
  • column is used herein to mean a distillation, rectification or fractionation column, i.e., a contacting column or zone wherein liquid and vapor phases are countercurrently contacted to effect separation of a fluid mixture, as for example, by contacting of the vapor and liquid phases on a series of vertically spaced trays or plates mounted within the column, or on packing elements, or a combination thereof.
  • a distillation, rectification or fractionation column i.e., a contacting column or zone wherein liquid and vapor phases are countercurrently contacted to effect separation of a fluid mixture, as for example, by contacting of the vapor and liquid phases on a series of vertically spaced trays or plates mounted within the column, or on packing elements, or a combination thereof.
  • top condenser is used herein to mean the respective primary column or auxiliary column condenser wherein vapor from the column is condensed to provide reflux by indirect heat exchange with vaporizing liquid at a lower pressure.
  • indirect heat exchange is used herein to mean the bringing of two fluid streams into heat exchange relation without any physical contact or intermixing of the fluids with each other.
  • Turboexpansion is used herein to mean the conversion of the pressure energy of a gas into mechanical work by expansion of the gas through a device such as a turbine.
  • FIG. 1 is a schematic representation of one embodiment of the invention.
  • FIG. 2 is a schematic representation of a preferred embodiment of the invention wherein feed air turboexpansion is employed to generate refrigeration.
  • FIG. 3 is a schematic representation of another preferred embodiment of the invention wherein a waste stream is turboexpanded to generate refrigeration.
  • feed air 1 is compressed by passage through compressor 2 and the resulting compressed feed air 3 is cleaned of high boiling impurities such as water vapor and carbon dioxide by passage through prepurifier 4.
  • prepurifier 4 comprises molecular sieve beds.
  • Compressed, cleaned feed air 5 is then cooled by passage through heat exchanger 6 by indirect heat exchange with return streams.
  • a portion 7 of the feed air is turboexpanded by passage through turboexpander 50 thus generating refrigeration, and this refrigeration is put into the nitrogen production system as resulting turboexpanded air stream 8 is provided into auxiliary column 200.
  • feed air portion 7 will be from about 5 to 20 percent of the incoming feed air 1.
  • FIG. 1 illustrates a preferred embodiment of the invention wherein a portion 10 of the feed air is liquified by passage through heat exchanger 11 by indirect heat exchange with return streams. Resulting liquified feed air portion 12 and gaseous feed air portion 13 are provided into primary column 100. If employed, liquified feed air portion 12 will comprise up to about 10 percent of incoming feed air 1.
  • the feed air is separated by cryogenic rectification into nitrogen-richer component and oxygen-enriched component.
  • the nitrogen-richer component will generally have a nitrogen concentration of at least about 99 percent and may have a nitrogen concentration of up to 99.9999 percent or more.
  • the oxygen-enriched component will generally have an oxygen concentration within the range of from 30 to 45 percent.
  • Gaseous nitrogen-richer component 14 may be passed out of primary column 100.
  • a portion 15 of the nitrogen-richer component is warmed by passage through heat exchangers 11 and 6 and recovered as product elevated pressure nitrogen gas 16.
  • the pressure of the product gas may be up to the operating pressure of the primary column less pressure drop in the recovery conduit.
  • Another portion 17 of the nitrogen-richer component is provided into primary column top condenser 101.
  • oxygen-enriched component taken as liquid stream 18 from or near the bottom of primary column 100.
  • stream 18 is cooled by passage through heat exchanger 11.
  • a portion 19 of cooled stream 18 is passed into top condenser 101 while another portion 20 is provided directly into auxiliary column 200.
  • nitrogen-richer component 17 is condensed by indirect heat exchange with oxygen-enriched component supplied to top condenser 101 such that the oxygen-enriched component is at least partially vaporized.
  • oxygen-enriched component is completely vaporized by the heat exchange within top condenser 101 and the resulting vapor is provided as stream 21 into auxiliary column 200 at or near the bottom of the column.
  • Resulting condensed nitrogen-richer component 28 is employed as liquid reflux for primary column 100. If desired, a portion of the nitrogen-richer component from top condenser 101 may be recovered as product liquid nitrogen.
  • Auxiliary column 200 operates at a pressure less than that of primary column 100. Generally the operating pressure of auxiliary column 200 will be within the range of from 40 to 70 psia, preferably within the range of from 45 to 60 psia.
  • the feed or feeds into the column are separated by cryogenic rectification into nitrogen-enriched vapor and oxygen-richer liquid.
  • the feed into auxiliary column 200 will include one or more streams of oxygen-enriched component and may also include a turboexpanded feed air stream.
  • the nitrogen-enriched vapor will have a nitrogen concentration within the range of from 90 to 100 percent and the oxygen-richer liquid will have an oxygen concentration within the range of from 45 to 65 percent.
  • Nitrogen-enriched vapor 22 and oxygen-richer liquid 23 are provided into auxiliary column top condenser 201 wherein nitrogen-enriched vapor is condensed by indirect heat exchange with vaporizing oxygen-richer liquid.
  • the resulting oxygen-richer vapor is passed from top condenser 201 as stream 24 through heat exchangers 11 and 6 and out of the system as stream 25.
  • the resulting nitrogen-enriched liquid is passed 26 into auxiliary column 200 as liquid reflux.
  • a portion 27 of the nitrogen-enriched liquid is increased in pressure to substantially that of primary column 100 and then provided into primary column 100.
  • a preferred means of increasing the pressure of the nitrogen-enriched liquid is by passing the liquid through a liquid pump such as liquid pump 60 illustrated in FIG. 1.
  • the pressurized nitrogen-enriched liquid may be conveniently provided into primary column 100 by combination with the liquid reflux stream 28.
  • the pressurized nitrogen-enriched liquid provided into primary column 100 enables the production of further nitrogen-richer component and consequent elevated pressure nitrogen product.
  • the pressurized recycled nitrogen liquid stream need not be combined with reflux stream 28, but rather may be inserted into the top section of primary column 100, for example, if its purity is slightly less than that of stream 28.
  • the recycled nitrogen liquid stream back to the primary column provides additional nitrogen liquid reflux so that a large gaseous nitrogen stream can be withdrawn from the top of the primary column to produce a gaseous nitrogen product stream at a single elevated pressure from the column system.
  • FIG. 2 illustrates a particularly preferred embodiment of the invention wherein a portion of the cooled, cleaned, compressed feed air is liquified by indirect heat exchange with auxiliary column bottoms prior to introduction into the primary.
  • the numerals in FIG. 2 correspond to those of FIG. 1 for the common elements and the descriptions of these common elements will not be repeated.
  • a portion 30 of the cooled, cleaned, compressed feed air is provided into bottom reboiler 202 wherein it is condensed by indirect heat exchange with vaporizing bottom liquid of auxiliary column 200 thus providing vapor boilup for auxiliary column 200.
  • Portion 30, if employed, may be from 1 to 30 percent of incoming feed air 1.
  • the remaining portion 34 of stream 13 is provided directly into column 100.
  • Resulting liquified air is passed as stream 31 into primary column 100.
  • vapor from primary column top condenser 101 need not be passed into the bottom of auxiliary column 200.
  • auxiliary column reboiler 202 increases the nitrogen recovery over that of the simpler arrangement illustrated in FIG. 1 by enriching the oxygen content of stream 23 which becomes the waste rejection stream 24. Passing the entire stream 18 into top condenser 101 is a feature which allows feed stream 1 to be at its lowest pressure for the column system.
  • FIG. 3 illustrates another preferred embodiment of the invention wherein a waste stream rather than a feed air stream is turboexpanded to generate refrigeration.
  • the numerals in FIG. 3 correspond to those of FIGS. 1 and/or 2 for the common elements and the description of these common elements will not be repeated.
  • feed air stream 5 fully traverses heat exchanger 6.
  • a portion 40 of oxygen-enriched vapor 41 from top condenser 101 is warmed by partial traverse of heat exchanger 6 while another portion 42 of oxygen-enriched vapor 41 is passed into auxiliary column 200.
  • Warmed oxygen-enriched vapor 43 is turboexpanded by passage though turboexpander 44 to generate refrigeration and the resulting turboexpanded stream 45 is passed through heat exchanger 6, such as by combination with stream 24, thus transferring added refrigeration to the incoming feed air and into the system.
  • the resulting warmed stream is removed from the system such as with waste stream 25.
  • the embodiment of the invention illustrated in FIG. 2 will enable the recovery of 56.5 percent of the incoming feed air as product elevated pressure nitrogen and the embodiment of the invention illustrated in FIG. 3 will enable the recovery of 54.9 percent of the incoming feed air as product elevated pressure nitrogen.
  • system refrigeration may be generated by the turboexpansion of a portion of the nitrogen-richer component from the primary column thus producing some nitrogen product at a lower pressure.
  • This alternative may be advantageous if some lower pressure nitrogen product is desired.
  • system refrigeration may be generated by turboexpansion of an oxygen enriched vapor stream taken from the auxiliary column.
  • One or both of the top condensers could be within their respective columns as opposed to outside as illustrated in the Figures.
  • the auxiliary column reboiler illustrated in FIGS. 2 and 3 could be outside the auxiliary column.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Separation By Low-Temperature Treatments (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
US07/644,228 1991-01-22 1991-01-22 Method and apparatus for producing elevated pressure nitrogen Expired - Lifetime US5098457A (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
US07/644,228 US5098457A (en) 1991-01-22 1991-01-22 Method and apparatus for producing elevated pressure nitrogen
EP92100936A EP0496355B1 (en) 1991-01-22 1992-01-21 Method and apparatus for producing elevated pressure nitrogen
JP4029078A JPH0789017B2 (ja) 1991-01-22 1992-01-21 高圧窒素の製造方法及び装置
ES92100936T ES2065715T3 (es) 1991-01-22 1992-01-21 Metodo y aparato para producir nitrogeno a presion elevada.
DE69200928T DE69200928T2 (de) 1991-01-22 1992-01-21 Verfahren und Vorrichtung zur Herstellung von Stickstoff unter erhöhtem Druck.
MX9200264A MX9200264A (es) 1991-01-22 1992-01-21 Metodo y aparato para producir nitrogeno a presionmetodo y aparato para producir nitrogeno a presion elevada. elevada.
CA002059774A CA2059774C (en) 1991-01-22 1992-01-21 Method and apparatus for producing elevated pressure nitrogen
KR1019920000773A KR0161296B1 (ko) 1991-01-22 1992-01-21 승압된 질소를 제조하기 위한 방법 및 장치
BR929200190A BR9200190A (pt) 1991-01-22 1992-01-22 Processo e equipamento para a producao de nitrogenio em pressao elevada

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US07/644,228 US5098457A (en) 1991-01-22 1991-01-22 Method and apparatus for producing elevated pressure nitrogen

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US5098457A true US5098457A (en) 1992-03-24

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US5233838A (en) * 1992-06-01 1993-08-10 Praxair Technology, Inc. Auxiliary column cryogenic rectification system
US5303556A (en) * 1993-01-21 1994-04-19 Praxair Technology, Inc. Single column cryogenic rectification system for producing nitrogen gas at elevated pressure and high purity
US5321953A (en) * 1993-05-10 1994-06-21 Praxair Technology, Inc. Cryogenic rectification system with prepurifier feed chiller
US5355681A (en) * 1993-09-23 1994-10-18 Air Products And Chemicals, Inc. Air separation schemes for oxygen and nitrogen coproduction as gas and/or liquid products
US5355682A (en) * 1993-09-15 1994-10-18 Air Products And Chemicals, Inc. Cryogenic air separation process producing elevated pressure nitrogen by pumped liquid nitrogen
US5385024A (en) * 1993-09-29 1995-01-31 Praxair Technology, Inc. Cryogenic rectification system with improved recovery
US5402647A (en) * 1994-03-25 1995-04-04 Praxair Technology, Inc. Cryogenic rectification system for producing elevated pressure nitrogen
EP0793070A2 (en) 1996-01-31 1997-09-03 Air Products And Chemicals, Inc. High pressure combustion turbine and air separation system integration
US5682762A (en) * 1996-10-01 1997-11-04 Air Products And Chemicals, Inc. Process to produce high pressure nitrogen using a high pressure column and one or more lower pressure columns
US5697229A (en) * 1996-08-07 1997-12-16 Air Products And Chemicals, Inc. Process to produce nitrogen using a double column plus an auxiliary low pressure separation zone
WO1998019122A1 (de) * 1996-10-30 1998-05-07 Linde Aktiengesellschaft Verfahren und vorrichtung zur gewinnung von druckstickstoff
US5836175A (en) * 1997-08-29 1998-11-17 Praxair Technology, Inc. Dual column cryogenic rectification system for producing nitrogen
US5906113A (en) * 1998-04-08 1999-05-25 Praxair Technology, Inc. Serial column cryogenic rectification system for producing high purity nitrogen
US5918482A (en) * 1998-02-17 1999-07-06 Praxair Technology, Inc. Cryogenic rectification system for producing ultra-high purity nitrogen and ultra-high purity oxygen
US5934104A (en) * 1998-06-02 1999-08-10 Air Products And Chemicals, Inc. Multiple column nitrogen generators with oxygen coproduction
US5983667A (en) * 1997-10-31 1999-11-16 Praxair Technology, Inc. Cryogenic system for producing ultra-high purity nitrogen
US6009723A (en) * 1998-01-22 2000-01-04 Air Products And Chemicals, Inc. Elevated pressure air separation process with use of waste expansion for compression of a process stream
EP0593703B2 (en) † 1992-04-13 2001-06-20 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Ultra-high purity nitrogen and oxygen generator and process
US6279345B1 (en) 2000-05-18 2001-08-28 Praxair Technology, Inc. Cryogenic air separation system with split kettle recycle
US6330812B2 (en) 2000-03-02 2001-12-18 Robert Anthony Mostello Method and apparatus for producing nitrogen from air by cryogenic distillation
US6494060B1 (en) 2001-12-04 2002-12-17 Praxair Technology, Inc. Cryogenic rectification system for producing high purity nitrogen using high pressure turboexpansion
US6499312B1 (en) 2001-12-04 2002-12-31 Praxair Technology, Inc. Cryogenic rectification system for producing high purity nitrogen
US6546748B1 (en) 2002-06-11 2003-04-15 Praxair Technology, Inc. Cryogenic rectification system for producing ultra high purity clean dry air
US6568208B1 (en) * 2002-05-03 2003-05-27 Air Products And Chemicals, Inc. System and method for introducing low pressure reflux to a high pressure column without a pump
US20050115404A1 (en) * 2003-12-02 2005-06-02 Honeywell International Inc. Gas generating system and method for inerting aircraft fuel tanks
US20060075779A1 (en) * 2004-10-12 2006-04-13 Paul Higginbotham Process for the cryogenic distillation of air
US20080127676A1 (en) * 2006-11-30 2008-06-05 Amcscorporation Method and apparatus for production of high-pressure nitrogen from air by cryogenic distillation
US20130000351A1 (en) * 2011-06-28 2013-01-03 Air Liquide Process & Construction, Inc. Production Of High-Pressure Gaseous Nitrogen
US20130042646A1 (en) * 2011-08-17 2013-02-21 Aire Liquide Process & Construction, Inc. Production of High-Pressure Gaseous Nitrogen
US20130042647A1 (en) * 2011-08-18 2013-02-21 Air Liquide Process & Construction, Inc. Production Of High-Pressure Gaseous Nitrogen
CN104048478A (zh) * 2014-06-23 2014-09-17 浙江大川空分设备有限公司 高提取率和低能耗污氮气提纯氮气的设备及其提取方法
CN108759307A (zh) * 2018-04-08 2018-11-06 佛山市佛钢气体有限公司 一种多段精馏制取高纯氮气装置及方法
US10852061B2 (en) 2017-05-16 2020-12-01 Terrence J. Ebert Apparatus and process for liquefying gases
WO2021242307A1 (en) 2020-05-28 2021-12-02 Praxair Technology, Inc. Enhancements to a dual column nitrogen producing cryogenic air separation unit
WO2021242309A1 (en) 2020-05-26 2021-12-02 Praxair Technology, Inc. Enhancements to a dual column nitrogen producing cryogenic air separation unit
WO2021242308A1 (en) 2020-05-26 2021-12-02 Praxair Technology, Inc. Enhancements to a dual column nitrogen producing cryogenic air separation unit
US11674750B2 (en) 2020-06-04 2023-06-13 Praxair Technology, Inc. Dual column nitrogen producing air separation unit with split kettle reboil and integrated condenser-reboiler

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EP0593703B2 (en) † 1992-04-13 2001-06-20 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Ultra-high purity nitrogen and oxygen generator and process
US5233838A (en) * 1992-06-01 1993-08-10 Praxair Technology, Inc. Auxiliary column cryogenic rectification system
US5303556A (en) * 1993-01-21 1994-04-19 Praxair Technology, Inc. Single column cryogenic rectification system for producing nitrogen gas at elevated pressure and high purity
US5321953A (en) * 1993-05-10 1994-06-21 Praxair Technology, Inc. Cryogenic rectification system with prepurifier feed chiller
US5355682A (en) * 1993-09-15 1994-10-18 Air Products And Chemicals, Inc. Cryogenic air separation process producing elevated pressure nitrogen by pumped liquid nitrogen
US5355681A (en) * 1993-09-23 1994-10-18 Air Products And Chemicals, Inc. Air separation schemes for oxygen and nitrogen coproduction as gas and/or liquid products
US5385024A (en) * 1993-09-29 1995-01-31 Praxair Technology, Inc. Cryogenic rectification system with improved recovery
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EP0823606A2 (en) * 1996-08-07 1998-02-11 Air Products And Chemicals, Inc. Process to produce nitrogen using a double column plus an auxiliary low pressure separation zone
EP0823606B1 (en) * 1996-08-07 2003-03-05 Air Products And Chemicals, Inc. Process to produce nitrogen using a double column plus an auxiliary low pressure separation zone
US5682762A (en) * 1996-10-01 1997-11-04 Air Products And Chemicals, Inc. Process to produce high pressure nitrogen using a high pressure column and one or more lower pressure columns
WO1998019122A1 (de) * 1996-10-30 1998-05-07 Linde Aktiengesellschaft Verfahren und vorrichtung zur gewinnung von druckstickstoff
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US5836175A (en) * 1997-08-29 1998-11-17 Praxair Technology, Inc. Dual column cryogenic rectification system for producing nitrogen
US5983667A (en) * 1997-10-31 1999-11-16 Praxair Technology, Inc. Cryogenic system for producing ultra-high purity nitrogen
US6009723A (en) * 1998-01-22 2000-01-04 Air Products And Chemicals, Inc. Elevated pressure air separation process with use of waste expansion for compression of a process stream
US5918482A (en) * 1998-02-17 1999-07-06 Praxair Technology, Inc. Cryogenic rectification system for producing ultra-high purity nitrogen and ultra-high purity oxygen
US5906113A (en) * 1998-04-08 1999-05-25 Praxair Technology, Inc. Serial column cryogenic rectification system for producing high purity nitrogen
US5934104A (en) * 1998-06-02 1999-08-10 Air Products And Chemicals, Inc. Multiple column nitrogen generators with oxygen coproduction
US6330812B2 (en) 2000-03-02 2001-12-18 Robert Anthony Mostello Method and apparatus for producing nitrogen from air by cryogenic distillation
US6279345B1 (en) 2000-05-18 2001-08-28 Praxair Technology, Inc. Cryogenic air separation system with split kettle recycle
US6494060B1 (en) 2001-12-04 2002-12-17 Praxair Technology, Inc. Cryogenic rectification system for producing high purity nitrogen using high pressure turboexpansion
US6499312B1 (en) 2001-12-04 2002-12-31 Praxair Technology, Inc. Cryogenic rectification system for producing high purity nitrogen
US6568208B1 (en) * 2002-05-03 2003-05-27 Air Products And Chemicals, Inc. System and method for introducing low pressure reflux to a high pressure column without a pump
US6546748B1 (en) 2002-06-11 2003-04-15 Praxair Technology, Inc. Cryogenic rectification system for producing ultra high purity clean dry air
US20050115404A1 (en) * 2003-12-02 2005-06-02 Honeywell International Inc. Gas generating system and method for inerting aircraft fuel tanks
US7081153B2 (en) 2003-12-02 2006-07-25 Honeywell International Inc. Gas generating system and method for inerting aircraft fuel tanks
US20070000380A1 (en) * 2003-12-02 2007-01-04 Honeywell International Inc. Gas generating system and method for inerting aircraft fuel tanks
US7306644B2 (en) 2003-12-02 2007-12-11 Honeywell International, Inc. Gas generating system and method for inerting aircraft fuel tanks
US20060075779A1 (en) * 2004-10-12 2006-04-13 Paul Higginbotham Process for the cryogenic distillation of air
US20080127676A1 (en) * 2006-11-30 2008-06-05 Amcscorporation Method and apparatus for production of high-pressure nitrogen from air by cryogenic distillation
US20130000351A1 (en) * 2011-06-28 2013-01-03 Air Liquide Process & Construction, Inc. Production Of High-Pressure Gaseous Nitrogen
US20130042646A1 (en) * 2011-08-17 2013-02-21 Aire Liquide Process & Construction, Inc. Production of High-Pressure Gaseous Nitrogen
US9097459B2 (en) * 2011-08-17 2015-08-04 Air Liquide Process & Construction, Inc. Production of high-pressure gaseous nitrogen
US20130042647A1 (en) * 2011-08-18 2013-02-21 Air Liquide Process & Construction, Inc. Production Of High-Pressure Gaseous Nitrogen
CN104048478A (zh) * 2014-06-23 2014-09-17 浙江大川空分设备有限公司 高提取率和低能耗污氮气提纯氮气的设备及其提取方法
CN104048478B (zh) * 2014-06-23 2016-03-30 浙江大川空分设备有限公司 高提取率和低能耗污氮气提纯氮气的设备及其提取方法
US10852061B2 (en) 2017-05-16 2020-12-01 Terrence J. Ebert Apparatus and process for liquefying gases
CN108759307A (zh) * 2018-04-08 2018-11-06 佛山市佛钢气体有限公司 一种多段精馏制取高纯氮气装置及方法
WO2021242309A1 (en) 2020-05-26 2021-12-02 Praxair Technology, Inc. Enhancements to a dual column nitrogen producing cryogenic air separation unit
WO2021242308A1 (en) 2020-05-26 2021-12-02 Praxair Technology, Inc. Enhancements to a dual column nitrogen producing cryogenic air separation unit
WO2021242307A1 (en) 2020-05-28 2021-12-02 Praxair Technology, Inc. Enhancements to a dual column nitrogen producing cryogenic air separation unit
US11674750B2 (en) 2020-06-04 2023-06-13 Praxair Technology, Inc. Dual column nitrogen producing air separation unit with split kettle reboil and integrated condenser-reboiler
US11933540B2 (en) 2020-06-04 2024-03-19 Praxair Technology, Inc. Dual column nitrogen producing air separation unit with split kettle reboil and integrated condenser-reboiler

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DE69200928T2 (de) 1995-07-06
ES2065715T3 (es) 1995-02-16
BR9200190A (pt) 1992-10-06
KR920014708A (ko) 1992-08-25
KR0161296B1 (ko) 1998-11-16
EP0496355B1 (en) 1994-12-21
EP0496355A1 (en) 1992-07-29
DE69200928D1 (de) 1995-02-02
CA2059774C (en) 1994-12-13
JPH0789017B2 (ja) 1995-09-27
JPH0571870A (ja) 1993-03-23

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